Conformal Selective Acting: Anytime-Valid Risk Control for RLVR-Trained LLMs

Hamed Khosravi; Xiaoming Huo

cs.LGMay 18, 2026

Conformal Selective Acting: Anytime-Valid Risk Control for RLVR-Trained LLMs

Authors: Hamed Khosravi, Xiaoming Huo

Organizations: Georgia Institute of Technology

Abstract

A local specialist LLM, fine-tuned with reinforcement learning from verifiable rewards (RLVR) on operator-local data, is installed in a regulated organization with per-deployment error budget $α$ . The operator needs a safety certificate for this deployment's stream at every round: no pooling across deployments, no waiting for a long-run average. Existing wrappers cannot deliver this on adaptive, online-updated streams: offline conformal-risk methods require exchangeability; online-conformal methods bound only long-run averages; non-exchangeable extensions are marginally valid; and the closest anytime wrapper, A-RCPS, controls marginal rather than selective risk. Using a (test statistic, validity guarantee, deployment rule) framework, we identify one empty cell forced by deployment requirements: e-process per threshold, selective risk, anytime-pathwise validity, max-certified-threshold rule. Conformal Selective Acting (CSA) fills it as a per-round wrapper maintaining a Ville-type e-process per threshold on a Bonferroni grid, evaluated against the RLVR filtration. Under predictable updates and isotonic-calibrated monotone risk we prove (i) an anytime-pathwise selective-risk bound $R_T^{\mathrm{act}}\leα+O(N_T^{-1/2})$ , (ii) rate-optimal certification matching $Θ(\barη^{-2}\log(1/δ))$ , and (iii) a horizon-independent release-rate gap. Across eight specialist benchmarks ( $480$ streams), sixteen adversarial distribution-shift cells ( $160$ streams), and five live Expert-Iteration RLVR cells with online LoRA over four base models in three architecture families ( $10{,}300$ rounds), CSA is the only method among ten compared that satisfies pathwise validity and non-refusing deployment on every cell. We do not propose a new LLM, training algorithm, or policy class; CSA is the deployment-side complement, orthogonal to the model, for operators who cannot use a frontier API.

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